Is Breast Milk Compatible with Medications?


Most moms will take some sort of medication while they are breastfeeding.  It is important to make sure that these medications are safe for the baby.  Whether it is an herb, high-dose vitamins, prescribed medication, or something else, finding accurate information as to the safety and efficacy of continued breastfeeding is important. However, many health care professionals prefer to tell breastfeeding mothers to stop breastfeeding or to express and discard her milk when she needs to take a medication.

Why, after all, are many medications allowed during breastfeeding? The good news is that most drugs are completely compatible with breastfeeding!  The following information will help you maneuver through the landmines of finding reliable information.

Are drug inserts reliable?

Drug inserts are not a reliable form of information as to the drug’s impact on baby via breast milk as the drugs are not tested on breastfeeding women.  To protect them from litigation, drug manufacturers place a blanket statement that their drug is not compatible with breastfeeding.  The Physician’s Desk Reference (PDR) is based on these drug inserts.  This can make finding correct information challenging and frustrating for both a breastfeeding mother and her doctor.

Are there any drugs which are safe to take while breastfeeding?

women taking medicine
Yes! In fact, most medications are considered safe to use while breastfeeding because the amount received by the child is minimal. There are some that are safer than others.  And there are typically multiple medications which can be prescribed for the same illness, so understanding which drug will have the least impact on a mother’s breast milk and baby are important considerations for a breastfeeding mother.

The benefits of taking a medication should always be weighed against its potential harm to a breastfeeding baby.  The known risks of formula should be weighed against the potential risk of the medication.  If a drug is not essential, delay its use until later.  This is true for many herbs as well.  Yet, when a mother has a need for medication, understanding how medications pass into breast milk and how a baby’s body metabolizes the drug can help a mother and her doctor make the most informed decision possible.

Only a small number of drugs should be avoided

According to the latest report from the American Academy of Pediatrics (AAP), “only a small number of drugs [should] be avoided by nursing mothers. For many pharmaceutical products, it has been established that the active ingredients do not pass into the milk. For others, the doses transmitted are too low to have significant effects on the infant. A small number of drugs, as well as products derived from plants, should be avoided or even prohibited.

Vigilance is particularly important during the first weeks of breastfeeding. Indeed, the younger the child is, the less his body is able to eliminate a certain number of molecules, in particular at the level of his liver (excretion in the bile, with re-absorption by the intestine) and his kidneys (elimination through the urine).

What is considered a safe amount of medication to receive via breast milk?

For most drugs, ingesting 10% of the maternal dose is considered safe. With some drugs (for example, fluconazole and metronidazole) the dose can be much higher than this.  And usually, the dose ingested is less than 1%.  Thus, most medications truly are compatible to take while breastfeeding.  This is especially true in light of the 1000s of studies that show the detrimental side effects of formula.

Where can I go for accurate information?

If you doctor recommends weaning or “pumping and dumping” your milk while taking a medication, make sure you talk with a lactation consultant first.  There are many great resources with research and information on drugs and their impact on babies via breastfeeding.  Arming yourself with knowledge, you can then share research and information with your doctor to select the most appropriate medication for your needs that will also allow you to continue nursing your baby.

Medications and Mother’s Milk by Thomas W. Hale, Ph.D. is an excellent resource book.  This website is another great resource for accurate breastfeeding and medications information as is the LactMed search on the sidebar of this article.

When treatment is truly not compatible with breastfeeding…

breastfeeding mom and doctor

This is a difficult time and breastfeeding mothers need lots of love, support and encouragement.  Is it possible to pump and dump (or freeze) your milk?  Sometimes breastfeeding need only be interrupted for a time (hours or days) and then can be resumed.  During this time, it is important to keep up your milk supply by pumping each time your baby feeds.  If you don’t have enough breast milk for your baby, you could use human donor milk or formula.  By pumping and keeping up your supply, you can then return to nursing as soon as it is safe to do so.

Read also: Breastfeeding in Special or Unusual Situations

Other times mothers need help and support in weaning.  Usually in this circumstance there is not time to wean slowly.  Care not only needs to be made at keeping the mother comfortable but supporting both mother and baby emotionally.  If you find yourself in this circumstance, rejoice in the wonderful nursing relationship you were able to have with your baby.  Every drop of breast milk was a precious gift and you should be very proud of yourself!  Also, remember that this is not the end of your relationship with your baby but the beginning of a new era.  With the warm and loving bond you have already forged, this next phase can be even better.

If your baby is under a year and you are concerned about giving formula, check to see if there is a human milk bank you can get donor milk from.  Alternatively, there may be friends in your local community who informally share human milk.


Although most of the drugs are safe for the child, it is still advisable to monitor his or her general condition. The mother must be vigilant to the appearance of possible side effects: jaundice (yellow skin), diarrhea, constipation, refusal to eat, drowsiness. In conclusion, regardless of the medicine, it is essential for breastfeeding women to talk to their doctor or pharmacist before taking or stopping any medication, keeping in mind that the risks are often minimal and that alternatives to breastfeeding exist.